Source Code
These source-code files are part of a reconstructed copy of Luminary 173, the
second (unflown) release of the Apollo 14 Lunar Module (LM) Apollo Guidance
Computer (AGC) software.
The reconstruction began with reconstructed source code for Luminary 178. Changes between revision 173 and 178 were backed out, as described by Luminary memo 167 (revision 1). The reconstruction was verified by matching memory-bank checksums to those listed in drawing 2021152N. Note that page numbers in the reconstructed code match those for the baseline log section mentioned in each file's changelog; the page numbers for a real Luminary 173 listing would be different. Comments from the original source code are prefixed with a single '#' symbol, whereas comments added later are prefixed by "##" or "###". Report any errors noted by creating an issue report at the Virtual AGC project's GitHub repository. |
008876,000002: ## Copyright: Public domain.
008877,000003: ## Filename: AGS_INITIALIZATION.agc
008878,000004: ## Purpose: A section of Luminary revision 173.
008879,000005: ## It is part of the reconstructed source code for the second
008880,000006: ## (unflown) release of the flight software for the Lunar
008881,000007: ## Module's (LM) Apollo Guidance Computer (AGC) for Apollo 14.
008882,000008: ## The code has been recreated from a reconstructed copy of
008883,000009: ## Luminary 178, as well as Luminary memo 167 (revision 1).
008884,000010: ## It has been adapted such that the resulting bugger words
008885,000011: ## exactly match those specified for Luminary 173 in NASA
008886,000012: ## drawing 2021152N, which gives relatively high confidence
008887,000013: ## that the reconstruction is correct.
008888,000014: ## Reference: pp. 213-217
008889,000015: ## Assembler: yaYUL
008890,000016: ## Contact: Ron Burkey <info@sandroid.org>.
008891,000017: ## Website: www.ibiblio.org/apollo/index.html
008892,000018: ## Mod history: 2019-09-18 MAS Created from Luminary 178.
008893,000019:
Page 213 |
008895,000021: # PROGRAM NAME: AGS INITIALIZATION (R47)
008896,000022:
008897,000023: # WRITTEN BY : RHODE/KILROY/FOLLETT
008898,000024:
008899,000025: # MOD NO. : 0
008900,000026: # DATE : 23 MARCH 1967
008901,000027: # MOD BY : KILROY
008902,000028:
008903,000029: # MOD NO. : 1
008904,000030: # DATE : 28 OCTOBER 1967
008905,000031: # MOD BY : FOLLETT
008906,000032:
008907,000033: # FUNCT. DESC.: (1) TO PROVIDE THE AGS ABORT ELECTRONICS ASSEMBLY(AEA) WITH THE LEM AND CSM STATE VECTORS
008908,000034: # (POSITION,VELOCITY,TIME) IN LEM IMU COORDINATES BY MEANS OF THE LGC DIGITAL DOWNLINK.
008909,000035:
008910,000036: # (2) TO ZERO THE ICDU, LGC AND AEA GIMBAL ANGLE COUNTERS SIMULTANEOUSLY IN ORDER TO ESTABLISH A
008911,000037: # COMMON ZERO REFERENCE FOR THE MEASUREMENT OF GIMBAL(EULER) ANGLES WHICH DEFINE LEM ATTITUDE
008912,000038: # (3) TO ESTABLISH THE GROUND ELAPSED TIME OF AEA CLOCK ZERO.(IF AN AEA CLOCK ZERO IS
008913,000039: # REQUESTED DURING THIS PROGRAM
008914,000040:
008915,000041: # LOG SECTION : AGS INITIALIZATION
008916,000042:
008917,000043: # CALLING SEQ : PROGRAM IS ENTERED WHEN ASTRONAUT KEYS V47E ON DSKY.
008918,000044: # R47 MAY BE CALLED AT ANY TIME EXCEPT WHEN ANOTHER EXTENDED VERB IS IN PROGRESS
008919,000045:
008920,000046: # SUBROUTINES
008921,000047: # CALLED :
008922,000048:
008923,000049: # NORMAL EXIT : ENDEXT
008924,000050:
008925,000051: # ALARM/ABORT : ALARM - BAD REFSMMAT - CODE:220
008926,000052: # OPERATOR ERROR IF V47 SELECTED DURING ANOTHER EXTENDED VERB.
008927,000053:
008928,000054: # ERASABLES
008929,000055: # USED : SAMPTIME (2) TIME OF :ENTER: KEYSTROKE
008930,000056: # AGSK (2) GROUND ELAPSED TIME OF THE AEA CLOCK :ZERO:
008931,000057: # AGSBUFF (140) CONTAINS AGS INITIALIZATION DATA (SEE :OUTPUT: BELOW)
008932,000058: # AGSWORD (1) PREVIOUS DOWNLIST SAVED HERE
008933,000059:
008934,000060: 05,2460 E6,1771 EBANK= AGSK
008935,000061: 40,2000 BANK 40
008936,000062: 32,2000 SETLOC R47
008937,000063: 32,2000 BANK
008938,000064:
008939,000065: 32,2005 COUNT* $$/R47
008940,000066:
008941,000067: 32,2005 34737 AGSINIT CAF REFSMBIT
008942,000068: 32,2006 70077 MASK FLAGWRD3 # CHECK REFSMFLG.
008943,000069: 32,2007 10000 CCS A
008944,000070: 32,2010 02017 TC REDSPTEM # REFSMMAT IS OK
Page 214 |
008946,000072: 32,2011 05600 TC ALARM # REFSMMAT IS BAD
008947,000073: 32,2012 00220 OCT 220
008948,000074: 32,2013 05503 TC ENDEXT
008949,000075:
008950,000076: 32,2014 00006 NEWAGS EXTEND
008951,000077: 32,2015 30014 DCA SAMPTIME # TIME OF THE :ENTER: KEYSTROKE
008952,000078: 32,2016 53772 DXCH AGSK # BECOMES NEW AEA CLOCK :ZERO:
008953,000079:
008954,000080: 32,2017 00006 REDSPTEM EXTEND
008955,000081: 32,2020 31772 DCA AGSK
008956,000082: 32,2021 53051 DXCH DSPTEMX
008957,000083: 32,2022 32172 AGSDISPK CAF V06N16
008958,000084: 32,2023 04616 TC BANKCALL # R1 = 00XXX. HRS., R2 = 000XX MIN.,
008959,000085: 32,2024 20334 CADR GOMARKF # R3 = 0XX.XX SEC.
008960,000086: 32,2025 05503 TC ENDEXT # TERMINATE RETURN
008961,000087: 32,2026 02036 TC AGSVCALC # PROCEED RETURN
008962,000088: 32,2027 44746 CS BIT6 # IS ENTER VIA A V32
008963,000089: 32,2030 60154 AD MPAC
008964,000090: 32,2031 00006 EXTEND
008965,000091: 32,2032 12014 BZF NEWAGS # YES, USE KEYSTROKE TIME FOR NEW AGSK
008966,000092:
008967,000093: 32,2033 00006 EXTEND # NO, NEW AGSK LOADED VIA V25
008968,000094: 32,2034 31051 DCA DSPTEMX # LOADED INTO DSPTEMX BY KEYING
008969,000095: 32,2035 02016 TC REDSPTEM -1 # V25E FOLLOWED BY HRS.,MINS.,SECS.
008970,000096: # DISPLAY THE NEW K
008971,000097:
008972,000098: 32,2036 06042 AGSVCALC TC INTPRET
008973,000099: 32,2037 77614 SET
008974,000100: 32,2040 01076 NODOFLAG # DONT ALLOW V37
008975,000101: 32,2041 77414 SET EXIT
008976,000102: 32,2042 02076 XDSPFLAG
008977,000103:
008978,000104: 32,2043 32172 CAF V06N16
008979,000105: 32,2044 04616 TC BANKCALL
008980,000106: 32,2045 20621 CADR EXDSPRET
008981,000107:
008982,000108: 32,2046 06042 TC INTPRET # EXTRAPOLATE LEM AND CSM STATE VECTORS
008983,000109: 32,2047 77634 RTB # TO THE PRESENT TIME
008984,000110: 32,2050 21574 LOADTIME # LOAD MPAC WITH TIME2,TIME1
008985,000111: 32,2051 34041 STCALL TDEC1 # CALCULATE LEM STATE VECTOR
008986,000112: 32,2052 27056 LEMPREC
008987,000113: 32,2053 77624 CALL # CALL ROUTINE TO CONVERT TO SM COORDS AND
008988,000114: 32,2054 64132 SCALEVEC # PROVIDE PROPER SCALING
008989,000115: 32,2055 16201 STODL AGSBUFF # (LEMPREC AND CSMPREC LEAVE TDEC1 IN TAT)
008990,000116: 32,2056 00015 TAT # TAT = TIME TO WHICH RATT1 AND VATT1 ARE
008991,000117: 32,2057 34041 STCALL TDEC1 # COMPUTED(CSEC SINCE CLOCK START B-28).
008992,000118: 32,2060 27042 CSMPREC # CALCULATE CSM STATE VECTOR FOR SAME TIME
008993,000119: 32,2061 77624 CALL
008994,000120: 32,2062 64132 SCALEVEC
008995,000121: 32,2063 16207 STODL AGSBUFF +6
Page 215 |
008997,000123: 32,2064 00015 TAT
008998,000124: 32,2065 56225 DSU DDV # CALCULATE AND STORE THE TIME
008999,000125:
009000,000126: 32,2066 03372 AGSK
009001,000127: 32,2067 24175 TSCALE
009002,000128: 32,2070 02215 STORE AGSBUFF +12D
009003,000129: 32,2071 77776 EXIT
009004,000130:
009005,000131: 32,2072 34753 CAF LAGSLIST
009006,000132: 32,2073 54333 TS DNLSTCOD
009007,000133:
009008,000134: 32,2074 32176 CAF 20SEC # DELAY FOR 20 SEC WHILE THE AGS
009009,000135: 32,2075 04616 TC BANKCALL # DOWNLIST IS TRANSMITTED
009010,000136: 32,2076 01736 CADR DELAYJOB
009011,000137:
009012,000138: 32,2077 31321 CA AGSWORD
009013,000139: 32,2100 54333 TS DNLSTCOD # RETURN TO THE OLD DOWNLIST
009014,000140: 32,2101 34744 CAF IMUSEBIT
009015,000141: 32,2102 70074 MASK FLAGWRD0 # CHECK IMUSE FLAG.
009016,000142: 32,2103 10000 CCS A
009017,000143: 32,2104 02122 TC AGSEND # IMU IS BEING USED - DO NOT ZERO
009018,000144: 32,2105 11301 CKSTALL CCS IMUCADR # CHECK FOR IMU USAGE WHICH AVOIDS THE
009019,000145: 32,2106 12111 TCF +3 # IMUSE BIT: I.E., IMU COMPENSATION.
009020,000146: 32,2107 12115 TCF +6 # FREE. GO AHEAD WITH THE IMU ZERO.
009021,000147: 32,2110 12111 TCF +1
009022,000148: 32,2111 34363 +3 CAF TEN # WAIT .1 SEC AND TRY AGAIN.
009023,000149: 32,2112 04616 TC BANKCALL
009024,000150: 32,2113 01736 CADR DELAYJOB
009025,000151: 32,2114 12105 TCF CKSTALL
009026,000152:
009027,000153: 32,2115 04616 +6 TC BANKCALL # IMU IS NOT IN USE
009028,000154: 32,2116 16700 CADR IMUZERO # SET IMU ZERO DISCRETE FOR 320 MSECS
009029,000155: 32,2117 04616 TC BANKCALL # WAIT 3 SEC FOR COUNTERS TO INCREMENT
009030,000156: 32,2120 17722 CADR IMUSTALL
009031,000157: 32,2121 02122 TC AGSEND
009032,000158: 32,2122 05527 AGSEND TC DOWNFLAG # ALLOW V37
009033,000159: 32,2123 00054 ADRES NODOFLAG
009034,000160: 32,2124 32173 CAF V50N16
009035,000161: 32,2125 04616 TC BANKCALL
009036,000162: 32,2126 20342 CADR GOMARK3
009037,000163: 32,2127 15503 TCF ENDEXT
009038,000164: 32,2130 15503 TCF ENDEXT
009039,000165: 32,2131 05503 TC ENDEXT
009040,000166:
009041,000167: 32,2132 64375 SCALEVEC VLOAD MXV
009042,000168: 32,2133 00025 VATT1
009043,000169: 32,2134 01732 REFSMMAT
009044,000170: 32,2135 72561 VXSC VSL2
009045,000171: 32,2136 24202 VSCALE
009046,000172: 32,2137 53255 VAD VAD # THIS SECTION ROUNDS THE VECTOR, AND
Page 216 |
009048,000174: 32,2140 24204 AGSRND1 # CORRECTS FOR THE FACT THAT THE AGS
009049,000175: 32,2141 24212 AGSRND2 # IS A 2 S COMPLIMENT MACHINE WHILE THE
009050,000176: 32,2142 77634 RTB # LGC IS A 1 S COMPLIMENT MACHINE.
009051,000177: 32,2143 21773 VECSGNAG
009052,000178: 32,2144 24025 STOVL VATT1
009053,000179: 32,2145 00017 RATT1
009054,000180: 32,2146 74321 MXV VXSC
009055,000181: 32,2147 01732 REFSMMAT
009056,000182: 32,2150 24200 RSCALE
009057,000183: 32,2151 53212 VSL8 VAD # AGAIN THIS SECTION ROUNDS. TWO VECTORS
009058,000184: 32,2152 24204 AGSRND1 # ARE ADDED TO DEFEAT ALSIGNAG IN THE
009059,000185: 32,2153 47055 VAD RTB # CASE OF A HIGH-ORDER ZERO COUPLED WITH
009060,000186: 32,2154 24212 AGSRND2 # A LOW ORDER NEGATIVE PART.
009061,000187: 32,2155 21773 VECSGNAG
009062,000188: 32,2156 77750 LXA,1
009063,000189: 32,2157 00024 VATT1
009064,000190: 32,2160 72130 SXA,1 LXA,1
009065,000191: 32,2161 00155 MPAC +1
009066,000192: 32,2162 00026 VATT1 +2
009067,000193: 32,2163 72130 SXA,1 LXA,1
009068,000194: 32,2164 00160 MPAC +4
009069,000195: 32,2165 00030 VATT1 +4
009070,000196: 32,2166 43530 SXA,1 RVQ
009071,000197: 32,2167 00162 MPAC +6
009072,000198:
009073,000199: 32,2170 4753 LAGSLIST = ONE
009074,000200: 32,2170 00216 V01N14 VN 0114
009075,000201: 32,2171 14400 V50N00A VN 5000
009076,000202: 32,2172 6010 V00N25 EQUALS OCT31
009077,000203: 32,2172 01420 V06N16 VN 0616
009078,000204: 32,2173 4242 V00N34 EQUALS 34DEC
009079,000205: 32,2173 14420 V50N16 VN 5016
009080,000206: 32,2174 03100 00000 TSCALE 2DEC 100 B-10 # CSEC TO SEC SCALE FACTOR
009081,000207: 32,2176 03720 20SEC DEC 2000 B-14
009082,000208: 32,2177 15077 05041 RSCALE 2DEC 3.280839 B-3 # METERS TO FEET SCALE FACTOR
009083,000209: 32,2201 24402 25724 VSCALE 2DEC 3.280839 E2 B-9 # METERS/CS TO FEET/SEC SCALE FACTOR
009084,000210: 32,2203 00000 60000 AGSRND1 2OCT 0000060000
009085,000211: 32,2205 00000 60000 2OCT 0000060000
009086,000212: 32,2207 00000 60000 2OCT 0000060000
009087,000213: 32,2211 00000 37777 AGSRND2 2OCT 0000037777
009088,000214: 32,2213 00000 37777 2OCT 0000037777
009089,000215: 32,2215 00000 37777 2OCT 0000037777
Page 217 |
009091,000217: 32,2217 30,2000 SBANK= LOWSUPER # FOR SUBSEQUENT LOW 2CADRS.
End of include-file AGS_INITIALIZATION.agc. Parent file is MAIN.agc